Mat



FIG. 1 is a front perspective view of a mat showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is an enlarged detail view thereof showing the portion identified in the reference bubble FIG. 5 in FIG. 1.

The broken lines in the drawings depict portions of the mat that form no part of the claimed design. 

CLAIM The ornamental design for a mat, as shown and described. 